Refrigeration apparatus



Jan. 16, 1934.= G, E HUL'SE' 1,943,963

REFRIGERATION APPARATUS Filed Sept. 20, 1930 INVENTOR ATTORNEYS Patented Jan. 16, 1934 UNITED. STATES 1,943,963 REFRIGERATION APPARATUS George E. Hulse, New Haven, Conn., assignor to The Safety Car Heating & Lighting Company, a corporation of New Jersey Application September 20, 1930 Serial No. 483,195

19 Claims.

This invention relates to refrigeration systems.

One of the objects of this invention is to provide a practical refrigerating system which Will be eflicient and dependable in operation. An-

other object is to provide a, dependable system of the above nature which automatically controls the speed of the prime mover of the refrigeration system in a simple and reliable manner. Another object is to provide a refrigerating system that will be of simple and inexpensive construction, and which in operation will require a minimum of manual attention. Another object is to provide a refrigerating system in which effective l5 and eflicient use may be made of a simple and inexpensive type of prime mover. is to provide a system of the above mentioned nature in which a preferably continually operating prime mover may be dependably controlled to meet the varying requirements of the intermittent operation of the refrigerating apparatus. Another object is to provide a system of the above nature in which the necessity for delicate adjustment is obviated, and which may nevertheless be readily controlled to meet conditions in use. Other objects will be in part obvious and in part pointed out hereinafter.

This invention accordingly consists in the features of construction, combination of elements,

arrangement of parts, and in the several steps and relation and order of each of the same to one or more of the others, all as will be illustratively described herein, and the scope of the 'application of which will be indicated in the following claims.

In the accompanying; drawing in which is shown one of the various possible embodiments of this invention,

Fig. 1 is a general view showing the arrange- 49 ment of parts in a refrigeration system in diagram and the speed adjusting device in detail,

Fig. 2 is the side elevation of the speed adjusting device.

Similar references and characters refer to similar parts throughout both views of the draw- As conducive to a clearer understanding of certain features of this invention, it may at this I point be briefly stated that in certain forms of 5 vehicles, such as railroad cars and trucks, the refrigerating systems are subject to certain peculiar requirements fundamentally based on an unbalanced working period of time. For instance one of these cars may be loaded with perishable goods, thus requiring immediate refrigeration.

Another object- A period of ten days or more may possibly elapse before this car is unloaded, and during this time the car may travel for long distances or be sidetracked at some place where there is little opportunity to adjust the refrigerating system. Fur- 69 thermore, what little attention the refrigerating systems of thesecars may get will be of an unskilled and probably careless nature. For this reason it is convenient to equip these cars with refrigeratingsystems of simple and reliable design. Also it is advantageous that these systems have durable means responsive to temperaature for regulating the rate of refrigeration. This invention aims to provide a simple and practical construction in an apparatus of the above 7 described character.

Referring now to the drawing in detail, there is shown in Fig. 1 in diagram an internal combustion engine 10 driving a generator 11 by means of driving members 12. At the opposite end of motor 10 there is diagrammatically shown an electrically actuated clutch 13 on the shaft 14. The shaft 14 drives a compressor 15 of any desired construction, this compressor being an element of a compression-expansion refrigerating system generally indicated at 15a. This apparatus 15a furnishes refrigeration for the chamber as by means of a coil 5. The clutch 13 is of the electro-mag'netic construction and is disposed between the engine 10 and the compressor 15. This clutch is of such a construction that it will not be actuated by current from the generator 11 when this generator is rotating at the idling speed of the engine. Only when the engine 10 and consequently the generator 11 increase speed will this clutch be actuated, thus transferring motion to the compressor 11.

At the point 16 on the motor there is shown diagrammatically a governor for the motor. This governor is constructed in any suitable manner, an example of which is a throttle valve 'on ,car whose temperature is to be regulated. Outside this chamber 6 is a second thermostatic switch 9a adapted to .be continuously closed when the temperature outside this chamber is above that preferred in the chamber.

This engine 10 is constructed in a manner to run continuously for long periods of time, such as two or three weeks. It is preferably of the Diesel compression-ignition design, and is small, compact, strong and light. By causing such an engine to operate continuously while controlling its operations so that refrigeration needs are adequately served, I have been able to simplify the construction and operation of such a refrigerating system greatly in that it eliminates complicated working parts. This further reduces the necessity for care and adjustment of the system and makes the system more admirably suited for trucks, railroad cars and the like.

A fixed preferably brass guide shaft 17 extends from the govemor to the opposite end of a frame 21 where it is secured to a suitable extension 2111 of this frame, as is better shown in Figure 2. It is desirable for this shaft to be made of some material, such as brass, which will not influence magnetic fields. Encircling this shaft 17 is a helical spring 18 extending along the shaft and having its one end acting upon the speed controlling means or governor 16 so that the pressure or tension exerted by this spring will determine the speed of operation of the motor 10 to be maintained by the governor. At the other end 19 of the spring 18 is a disk-like metallic member 20 apertured near its center to allow a passage for the rod 17. This metallic member or washer 20 is secured in any suitable manner to the end 19 of the spring 18.

Opposite the spring 18 andsecured to the frame 21 so that its core 23 will be in substantial axial alignment with the guide rod 17 is a solenoid 22. The winding of the solenoid 22 and the electrically actuated clutch 13 are connected in series with the generator 11 so that current from this generator will serve the clutch 13 and energize the solenoid 22. The shaft 17 extends through the center of the solenoid 22.

Mounted on the shaft 1'7 is the sliding core 23 of the solenoid 22. This core is so constructed that it may slide along the entire length of the shaft 17 with ease, and at that end of this core which is closest to metallic member 20 is a brass extension 24 of the core. This extension is secured to the core 23 and to the metallic member 20. It will be seen that by this construction the core 23, the extension 24, the metallic member 20 and the end 19 of the spring 18 become a unit capable of sliding along the axis of the shaft 1'7 according to the relative tensions of this spring and the solenoid when it is energized.

Mounted to one side of this device generally indicated by the numeral 35 is a metallic member 25 positioned so that its end 26 lies in the path of the metallic member 20 as. member 20 slides along the shaft 17. This abutting member 26 is so positioned that it will come in contact with only this metallic member 20 and not interfere with the longitudinal motion of the core 23 or the core extension 24. Extending through the base 251: of this metallic member 25 is a guiding shaft 2'7 secured at its opposite ends to a frame generally indicated at 28 as is more clearly shown in Fig. 2. Mounted on this same frame 28 and passing through the metallic member 25 at a point 29 is a threaded shaft 33 capable of rotation and being manually operated by the thumb screw 30. At the opposite end of the metallic member 25 is a pointer 31 in registry with a scale 32. I

By adjusting the thumb screw 30, thus moving 20 at its end abuts with the element 26.

along the axis of the elements 35, the abutting element 26 may be brought to rest in any desired position in this plane. Thus when solenoid 22 is energized by the generator 11 and exerts a tension through its core 23 on the spring 18, this spring will slide along the shaft 17 relieving pressure on the governor 16 until the metallic member This increases the speed of the engine according to the position of this abutting element.

Turning now to the operation of this refrigerating system and more particularly to the speed adjusting device as herein outlined, it may first be assumed that the motor 10 has been started by any means (not described herein) and that the temperature in the cooled chamber is above that preferred and refrigeration is desired. The outside thermostat 9a is closed because air outside the chamber is above the preferred tem perature. The thermostatic switch 9 has been previously adjusted to close when such a temperature has been reached, and upon this action a circuit 8 between the generator 11 and the solenoid 22 will be closed. It should also be noted as described above that circuit 7 is continuously closed between generator 11 and the magnetic clutch 13. It is also assumed in this illustration that rapid refrigeration is required so that a maximum amount of speed must be attained from the engine 10 to drive the compressor 15 at high speed. Such a condition will result in a refrigerated railroad car just after it is loaded with perishable goods, and in such a case it would be necessary to lower the temperature of these goods immediately. If such a condition is desired, the metallic element 25 will be moved along the threaded shaft 33 toward the solenoid 22 until the abutting element 26 is brought to a position which will insure the preferred maximum speed of the engine.

When the solenoid 22 is energized, its magnetic field creates a tension on the core 23 and thus on the spring 18. This tension will pull the spring 18 out to the abutting element 26, thus relieving the pressure power of the spring 18 relatively according to the position of the metallic member 25. As described above the governor 16 is of such a construction that a release of pressure applied on it by the spring 16 will increase the speed of the engine 10. Simultaneously with the increased speed of the engine the'generator 11 is driven at a proportionately greater rate of speed, thus producing enough current to actuate the clutch 13 andset the compressor 15 in motion.

Refrigeration will continue in this manner until the preferred temperature has been reached, when the thermostatic switch 9 will be thrown open, thus breaking the circuit between the generator 11 and the solenoid 22. This releases the tension on the core 23, and the compression spring 18 will spring back to its normal position creating its normal pressure on the governor 16 and slowing the engine to minimum 1 or idling speed. As the speed of the engine is decreased, the generator 13 will not furnish sufficient current to actuate the clutch 13 so "that shaft 14 of the engine will be thrown out of connection with the compressor 15, and the moving parts of the refrigerator unit will stop.

Assuming that the above described quick. or rapid refrigeration, upon the car having been loaded, has been initially achieved substantially as above described, the engine 10 will continue metallic member 25 in a longitudinal direction to operate at its minimum or idling speed until rise in temperature within the chamber 6 causes the thermostatic switch 9 to close, thus effecting an energization of the solenoid 22, the latter in turn resetting the governor 16 to cause the en-.

gine 10 to run at its maximum speed, as determined by the setting of the stop member 25, with consequent actuation of theclutch 13 and of the driven parts of the refrigerating unit. It may, however, be desired and in fact it is preferable to have the engine 10, after being again speeded up after this initial rapid rate.

of refrigeration has been achieved, operate at a speed greater than its idling speed but less than the above assumed maximum speed; in that case, after this initial rapid rateof refrigeration has been terminated, the stop member 25, may be reset so that the governor 16 is in turn reset, upon this subsequent energization of the solenoid 22, to maintain such an intermediate speed. This new standard of speed may thus be suited to the operating characteristics of the engine, or to the particular refrigeration requirements imposedby such factors as the character of the goods being refrigerated or for example, the atmospheric or climatic conditions in which the refrigerator car is operating, and this new standard of speed will thereafter be maintained every time that the thermostatic switch 9 is closed and for such periods of time as it remains closed.

In the intervening periods of time, that is, when the thermostatic switch 9 is open or when the thermostatic switch 9a prevents the thermostatic switch'9 from completing the circuit of the solenoid 22, the engine operates at its idling speed and is, of course, disconnected from the driven element of the refrigerator unit. Should the outside temperature be sufliciently low'so that actuation of the refrigerating unit is not 1 needed, the thermostatic switch 9a opens, insuring that the engine 10 continues to operate at its idling speed as long as the outside temperature continues low enough not to require mechanical refrigeration of the chamber 6.

A switch 9b may be provided which when closed short circuits the outside thermostat 9a making when the-cars are not in use, and on the other handquick refrigeration is often desired when a fresh load of perishable goods is acquired. For example, the car may be unloaded and in this condition requires no refrigeration. Upon receiving a load of perishable goods, quick refrigeration is desired, but after the preferred temperature is reached the rate of refrigeration may be reduced in order to economize on fuel and wear of parts. If a controlling system of the above described characteris employed, the engine may be started at its minimum or idling speed any time during the process of loading.

After the car is loaded the abutting elements 26 may be so adjusted that maximum speed of refrigeration is attained. After the preferred temperature has been reached, the abutting elements 26 can be moved in toward the spring 18, cutting ,down the speed of the engine and thus the rate of the refrigeration to any desired maximum. It

will be understood that this invention is not limited to use of such vehicles, the above explanation merely being essential to a clear understanding of its valuable features. This invention is particularly adaptedfor regulating and maintaining the speed of a continuously operated Diesel engine in such a system; It will be seen that it is suited for' use in railroad cars and trucks where labor unskilled in the art must care for the apparatus while it is in operation. The nature of this invention reduces this care to a minimum.

Moreover, the system and ap aratus of this invention makes it possible rea y' and conveniently to meet the varying and unusual conditions to which a refrigerating vehicle is subjected. For example, if the vehicle is operating in a relatively warm climate or durin'gthe sum- I mer, the stop member 25 is so positioned that, during the periods of operation of the refrigerator unit, the engine 10 operates at a higher speed and higher power output to meet the greater demands for refrigeration imposed upon continued relatively high rate of refrigeration is v cold weather, I may so set the controlling mechanism that, during the intervals of time determined by the thermostatic switch or switches, the engine 10 operates at a relatively low speed and low power output in order correspondingly to. meet the requirement for "a lower rate of refrigeration, or I may so set the controlling mechanism that the engine continuously operates at a speed above its idling speed and thus continuously supply a relatively low rate of refrigeration commensurate with the rate. of heat entry into the refrigerator chamber,

Furthermore, the system and apparatus will be seen to be of such flexibility of control that the relative lengths of time intervals of simple idling of the engine 10 and of driving of the refrigerating unit may be proportioned to suit any of the varied and peculiar conditions imposed either by the weather, climate, capacity of the refrigerator unit, characteristics of the driving motor, or.like and other factors. I

It will thus be seen that there is provided apparatus in which the several objects of this invention are achieved. This apparatus is of such simple construction and design that the various objects and the various elements will continue to function after long use with little repair. Furthermore, this apparatus is economical in the use of fuel as the engine is not subjected to a load until refrigeration is desired, and the maximum speed of this engine may be decreased to any desired degree in order to further economize on fuel.

As many possible embodiments may-be made in the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that. all matter hereinbefore set forth or. shown in the accompanying drawing is to be interpreted as illustrative an not in alimiting sense. a

I claim: 1. In a temperature regulating system, in combination, enclosing means for medium whose tem-: perature is to be regulated, a refrigerating unit for the interior of said enclosing means, motive means for an element of said refrigerating unit, a clutch disposed between said motive means and said element, temperature responsive means for controlling the speed of said motive means and controlling said clutch.

2. In a temperature regulating system, in combination, enclosing means for a medium whose temperature is to be regulated, a refrigerating unit for the interior of said enclosing means, motive means for an element of said refrigerating unit, a clutch disposed between said motive means and said element, means for controlling the speed of said motive means, and thermostatic means for controlling said speed-controlling means and said clutch.

3. In a temperature regulating system, in combination, a chamber for a medium whose temperature is to be regulated, a refrigerating unit for said chamber, said unit including a compressor, a motor for driving said compressor, a clutch disposed between said motor and said compressor, electro-magnetic means for controlling the speed of said motor, and a thermostatic switch for controlling said electro-magnetic means and said clutch.

4. In a temperature regulating system, in combination, a chamber for a medium whose temperature is to be regulated, a refrigerating unit for said chamber, said unit including. a compressor, a motor for driving said compressor, a clutch disposed between said motor and said compressor, electro-magnetic means for controlling the speed of said motor, stopping means for setting the standard of operation of said speed-controlling means, a thermostatic switch in said chamber, and a thermostatic switch outside said chamber, said switches controlling the action of said electro-magnetic means and said clutch.

5.- In a temperature regulating system, in combination, a chamber for a medium whose temperature is to be regulated, a refrigeration unit for said chamber, said unit including a compressor, an internal combustion engine adapted to run continuously for substantial periods of time actuating said compressor, a clutch disposed between said engine and said compressor, electro-magnetic means for controlling the speed of said engine, stopping means for setting the standard of operation of said speed controlling means, a thermostatic switch in said chamber, and a thermostatic switch outside said chamber, said switches controlling the action of said electro-magnetic means and said clutch.

6. In a temperature regulating system, in combination, a chamber whose temperature is to be regulated, a refrigeration unit for said chamber, motive means for said refrigeration unit, speed controlling means for said motive means, electromagnetic means adapted to actuate said speed controlling means, and thermostatic switches responsive to, the temperatures inside said chamber and outside said chamber, said switches being in the circuit of a source of current and said electro-magnetic means.

'7. In a temperature regulating system, in combination, a chamber whose temperature is to be regulated, a refrigeration unit for said chamber, motive means for said refrigeration unit, speed controlling means for said motive means, electromagnetic means adapted to actuate said speed controlling means, a generator driven by said motive means for supplying current to said electro-magnetic means, and thermostatic switches outside said chamber and inside said chamber respectively and in the circuit between said generator and said electro-magnetic means.

8. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to drive certainparts of said refrigeration unit, said internal combustion engine adapted to run continuously for the entire period of time when the temperature of said space is to be regulated whether or not said space needs refrigerating, a governor for selecting the operative speeds of said engine to determine whether said engine idles to make said refrigeration unit ineffective or runs at a speed sufficient 'to make said refrigeration unit effective, electrical means for controlling the operation of said governor, and a thermostatic switch responsive to the temperature of said space for controlling the circuit of said electrical means.

' 9. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internalcombustion engine adapted to drive certain parts of said refrigeration unit, said internal combustion engine adapted to run continuously for the entire period of time when the temperature of said space is to be regulated whether or not said space needs refrigerating, a governor for selecting the operative speeds of said engine to determine whether said engine idles to make said refrigeration unit ineffective or runs at a speed sufiicient to make said refrigeration unit effective, electrical means connected with said governor and adapted when energized to set said governor for said fast speed and when deenergized to set said governor for said idling speed, a source of current, a circuit between said source of current and said electrical means, and a thermostatic switch in thermal contact with said space in said circuit.

10. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to drive certain parts of said refrigeration unit, said internal combustion engine adapted to run continuously for the entire period of time when the temperature of said space is to be regulated whether or not said space needs refrigerating, a governor for selecting the operative speeds of said engine to determine whether said engine idles to make said refrigeration unit ineffective or runs at a speed sufficient to make said refrigeration unit effective, electrical means connected with said governor and adapted when energized to set said governor for said fast speed and when deenergized to set said governor for said idling speed, a source of current, a circuit between said source of current and said electrical means, a thermostatic switch responsive to the temperature of said space in said circuit, and a thermostatic switch responsive to the temperature outside of said space in said circuit.

11. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to drive certain parts of said refrigeration unit, said engine adapted to run for comparatively long periods of time during 'which the temperature of said space is being regulated whether or not the temperature of said space requires the operation of said refrigeration unit, a governor for said engine adapted to regulate the speed thereof, said governor having a part which when in one position causes said engine to operate at an idling speed and when extended from that position increases the speed of said engine in substantial proportion to the distance which it is moved, electrical means connected to said part and adapted to extend said part when energized, a source of current, a circuit between said source of current and said electrical means, and a thermostatic switch responsive to the temperature of said space in said circuit.

12. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to drive certain parts of said refrigeration unit,

said engine adapted to run for comparatively long periods of time during which the temperature of said' space is being regulated whether or not the temperature of said space requires the operation of said refrigeration unit, a governor for said engine adapted to regulate the speed thereof, said governor having a part which when in one position causes said engine to operate at an idling speed and when extended from that position increases the speed of said engine in substantial proportion to the distance which it is moved, electrical means connected to said part and adapted to extend said part when energized, a source of current, a circuit between said source of current and said electrical means, a thermostatic switch responsive to the temperature of said space in said circuit, and means for predetermining the maximum distance throughout which said part may be extended by said electrical means.

' 13. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to drive certain parts of said refrigeration unit, said engine adapted to run for comparatively long periods'of time during which the temperature of said space is being regulated whether or not the temperature of said space requires the operation "of said refrigeration unit, a governor for said engine adapted to regulate the speed thereof, said governor having a part which when in one position causes said engine to operate at an idling speed and when extended from that position increases the speed of said engine in substantial proportion to the distance which it is moved, electrical means connected to said part and adapted to extend said part when energized, a source of current, a circuit between said source of current and said electrical means, a thermostatic switch responsive to the temperature of said space in said circuit, a thermostatic switch responsive to the temperature outside of said space in said circuit, and means for predetermining the maximum distance throughout which said part may be extended by said electrical means,

14. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit, a governor for said engine adapted to hold said engine at said idling speed and when actuated to change the speed ofesaid engine to said increased speed, and means responsive to the temperature of said space for controlling the actuation of said governor.

15. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit, a governor for said engine adapted to hold said engine at said idling speed and when actuated to change the speed of said engine to said increased speed, and means responsive to the temperatures inside said space and outside said space for controlling the actuation of said governor.

16. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit, a governor for said engine adapted to hold said engine at said idling speed and when actuated to change the speed of said engine t'o-said increased speed, means responsive to the temperature of said space for controlling the actuation of .said governor, and means for changing at will said increased speed allowed by said governor.

' 1'7.- In a temperature regulating system, in T combination, means forming a space whose temperatureis to be regulated, a refrigeration unit for said space-an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit, a governor for said engine adapted to hold said engine at said idling speed and when actuated to change the speed of said engine to said increased speed, and means responsive to the temperature'outside said space for controlling the actuation of said governor.

18. In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit,a governor for said engine adapted to hold said engine at said idling speed and when actuated to change the speed of said engine to said increased speed, electrical means for actuating said governor, a source of current, a circuit between said source of current and said electrical means, and a thermostatic switch in said circuit responsive to the temperature of said space.

19.- In a temperature regulating system, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, an internal combustion engine adapted to run for substantial periods of time at an idling speed or at an increased speed and adapted to drive an element of said refrigeration unit, a governor for said engine adapted to hold 1 said engine at said idling speed and when actua ated to change the speed of said engine to said increased speed, electrical means for actuating said governor, a source of current, a circuit between said source of current and said electrical means, a thermostatic switch in said circuit responsive to the temperature of said space, and a second thermostatic switch in said circuit responsive to the temperature outside said space;

GEORGE E.- HULSE. 

